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<a name="MPI-Wisdom-Communication"></a>
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Previous: <a href="MPI-Plan-Creation.html#MPI-Plan-Creation" accesskey="p" rel="prev">MPI Plan Creation</a>, Up: <a href="FFTW-MPI-Reference.html#FFTW-MPI-Reference" accesskey="u" rel="up">FFTW MPI Reference</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<a name="MPI-Wisdom-Communication-1"></a>
<h4 class="subsection">6.12.6 MPI Wisdom Communication</h4>

<p>To facilitate synchronizing wisdom among the different MPI processes,
we provide two functions:
</p>
<a name="index-fftw_005fmpi_005fgather_005fwisdom-1"></a>
<a name="index-fftw_005fmpi_005fbroadcast_005fwisdom-1"></a>
<div class="example">
<pre class="example">void fftw_mpi_gather_wisdom(MPI_Comm comm);
void fftw_mpi_broadcast_wisdom(MPI_Comm comm);
</pre></div>

<p>The <code>fftw_mpi_gather_wisdom</code> function gathers all wisdom in the
given communicator <code>comm</code> to the process of rank 0 in the
communicator: that process obtains the union of all wisdom on all the
processes.  As a side effect, some other processes will gain
additional wisdom from other processes, but only process 0 will gain
the complete union.
</p>
<p>The <code>fftw_mpi_broadcast_wisdom</code> does the reverse: it exports
wisdom from process 0 in <code>comm</code> to all other processes in the
communicator, replacing any wisdom they currently have.
</p>
<p>See <a href="FFTW-MPI-Wisdom.html#FFTW-MPI-Wisdom">FFTW MPI Wisdom</a>.
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